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<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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  <style>
    div > span > a{
      color: red;
    }

    .color {
      color: red;
    }
  </style>
   <script src="https://cdn.bootcdn.net/ajax/libs/vue/3.5.13/vue.cjs.js"></script>
   <script src="https://cdn.bootcdn.net/ajax/libs/vue/3.5.13/vue.esm-browser.js"></script>
</head>

<body>
  <h1>hello world</h1>
  <img src="https://t7.baidu.com/it/u=1732966997,2981886582&fm=193&f=GIF" alt="">
  <img src="https://t7.baidu.com/it/u=1785207335,3397162108&fm=193&f=GIF" alt="">
  <img src="https://t7.baidu.com/it/u=245883932,1750720125&fm=193&f=GIF" alt="">
  <img src="https://t7.baidu.com/it/u=3423293041,3900166648&fm=193&f=GIF" alt="">
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  <script>
    const observer = new PerformanceObserver((list)=>{
        const entries = list.getEntries();
        for(let item of entries){
            if(item.name =='first-contentful-paint'){
                console.log('白屏时间',item.startTime,'ms');
            }
        }
    })
    observer.observe({type:'paint', buffered: true})
  </script>
</body>

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